Lathe-chuck



(No Model.)

J. N. SKINNER.

LATHE CHUCK.

Patented Jan. 2, 1883.

1723167450). W fl/vm' v fizi. iw; Mitwwe in y improved chuck.

UNTTED STATES PATENT OFFICE.

JAMES N. SKINNER, OF NEW BRITAIN, CONNECTICUT.

LATHE-CHUCK.

SPECIFICATION forming part of Letters Patent No. 269,889, dated January 2, 188

Application filed September 14. 1882.

To all whom it may concern:

Be it known that 1, JAMES N. SKINNER, of New Britain, in the county of Hartford and State of Connecticut, have invented certain new andusefulImprovementsin Lathe-Chucks; and I do hereby declare that the following is a full, clear, and exact description thereof,whereby a person skilled in the art can make and use the same, reference being bad to the accompanying drawings, and to the letters of reference marked thereon,

Like letters in the figures indicate the same parts.

My improvement relates to what are known as lathe-chucks, intended to hold a revolving tool for operating upon articles in a lathe such as a-drill-and also for holding any object which it is wished to revolve to be operated upon by stationary tools.

The object of my invention is to provide a small chuck which shall be simpler in its construction than the more complicated larger chucks, so that itcan easily be made sufficiently small to hold the smallest tools or articles, and also to provide a simpler construction for the larger sizes for ordinary use. I

In the accompanying drawings, illustrating my invention, Figure 1 shows a front view of Fig. 2 shows a top view of the same. Fig. 3 is a longitudinal vertical section through the middle of the chuck. Fig. 4 is a rear view with the revolving back plate removed to show the interior construction.

A A" A are three parts or sectors, which, united form the circular face-plate and body of the chuck.- These parts, when united, form a cylindrical body or stock, having a circular flange at its forward end for the face-plate. It is made in three parts, separated on radial lines for facility of construction, to permit the sockets and openings for the interior working parts to be more readily and easily out in the metal.

B-B B are thejaws. They project from the face-plate in the customary manner, and may be made of any of the usual forms to hold drills or other articles. As shown in the drawings, they are intended to hold a drill or round bar. The jaws are provided with projections B, which move out or in radially in slots in the (No model.)

face-plate, cut so as to lie one-half within the adjacentsectorsi'ormin g the bod y ofthe chuck.

C C C are screws for moving thejaws. They are furnished with bevel-gear wheels D, by which they are turned, as will be described. One half of these screws and gears lie within the thickness of the face-plate, which is furnished with sockets to receive them. The sockets serve as bearings for the gear-wheel, so that the screws cannot move out or in radially, and the thread of the screw workingin a hollow thread or nut in the projection B, the jaws are moved whenever the gears are revolved.

E is a ring lyingjust back of and close to the face-place and containing the other halfof the sockets for the screws 0 and gears D. This ring lies close against the face-place and is held in place by dowels or pins, so thatit cannot turn upon it. It thus practically forms part of the face-plate, but is made in a separate piece for convenience in cutting the sockets for the screws and their gears. It may be made as a simple ring provided with sockets for thecylindrical part of the shank of the screws outside of the gears, so as to hold the screws in place, but is preferably made to fit upon the central body of the chuck.

F 'is a revolving annular plate, forming the back plate of the chuck. It is furnished with a projecting ring, F, upon its face, which contains a circular beveled rack, gearing into the gear-wheels D. When this plate is revolved it turns the screws C and moves the jaws B out or in simultaneously.

G is a nut which screws upon the rear end of the body A of the chuck, formed by the three parts A, 800., before described. It rests against a shoulder at the lower end of the screw, so that when it is turned up tight it holds all the parts of the chuck together; but is not so tight as to prevent the turning of the plate F.

His a plug screwed into the hole which runs through the center of the body A, and lills its rear end. Its purpose is to strengthen and support the body and hold the three parts of which it is composed in their exact position.

J is a continuation of the nut Gr to the rear, for the purpose of forming a connection with the spindle of a lathe. It is provided with a socket, J, which is furnished with a hollow screw-thread fitting the screw on the lathespindle.

In order to adjust thejaws of my improved chuck so that. they may be all equidistant from the center, or, if desired, to set them at any other position, I provide the outer ends of the spindles of the screws C with slots G, by which they can be turned independently of each other. 3y loosening the nut G and drawing back theplate F, so that the circular rack becomes disengaged from the wheels D, either screw can he turned independently by means of a screw-driver and thejuw set as far out or in as desired. The plate F is furnished around its outer rim with milling or a roughened surface, by which it is easily turned to set and clamp thejaws upon the article to be held. It

is also provided with holes for a spanner or wrench to force it up tightly and give a firmer grip to thejaws when desired.

Vhat I claim as myinvention is- 1. In a lathe-chuck, the combination of the parts A A A, forming the body and face- 25 plate, the jaws B, the screws 0, having the gear-wheels D, the ring, E, the back plate haviug the circular rack F and the nut G, substantially as described.

2. In a lathe-chuck, the bodyand face-plate 3o composed of the radial sectors A A A, sub stantially as described.

3. In a lathe-chuck, the combination of the three sectors A A A. forming the body and vface-plate,with the nut G and the plug H,sub- 35 stantially as described.

7 JAMES N. SKINNER. Witnesses:

THEo. G. ELLIS, EDWIN F. DIMUCK. 

